Fangio’s departure as the Bears’ defensive coordinator to become the Broncos’ head coach left Bears fans in a funk of angst, anger and disappointment. But regardless of how the Bears replace Fangio, the 2019 season is all about Nagy, Mitch Trubisky and the Bears’ offense taking a huge step forward in Year 2.

Fangio’s departure is a big loss, but a natural course of events for successful football teams. It’s only a surprise because Fangio is 60 and a defensive coach in an era in which everybody seems to be looking for a quarterback whisperer. His window of opportunity seemed narrower than ever. Good for him that he finally was the right guy at the right place at the right time.

But if the Bears couldn’t afford to lose him, they would’ve hired him as head coach last year. The whole point of hiring Nagy is that the offense becomes the star of the show. Whatever step back the defense might take without Fangio — and don’t count on that, Packers, Vikings and Lions fans — should be offset by pretty significant improvement from Nagy’s offense.

The Bears' offense is looking to take a big step in 2019 with Matt Nagy in his second year working with Mitch Trubisky (10) and the offense. | Nam Y. Huh/AP photo

Losing productive coordinators has had an adverse effect on the Falcons and Vikings — recent Super Bowl contenders who didn’t make the playoffs this season. But those teams already had highly ranked units on the head coach’s side of the ball. The Bears under Nagy are just getting started.

As the late, great Al McGuire used to say, “The best thing about freshmen is they become sophomores.” The Bears’ offense is at that point. After a promising — but unfulfilling — first season with Nagy, the Bears return the bulk of the unit that laid the foundation.

“It’s a huge advantage,” tight end Trey Burton said. “You’ll hit the ground running instead of trying to do the very beginning of the foundation of a team. We know we can be a good team. The sky’s the limit for us next year.”

With Trubisky fully established as the team’s leader, the Bears will go into the offseason program working toward Week 1 of the regular season. When offseason practices began last year, Trubisky almost literally was introducing himself to Burton and wide receivers Allen Robinson, Taylor Gabriel and Anthony Miller. Now they’ll be working on stuff they’ve worked on 100 times over, able to communicate with a nod instead of a discussion.

“We all know each other,” Robinson said. “We all know the system. We all know the plays. We all know the checks. And I think that’s what makes it so much more exciting now. April 3 last year we were just trying to figure out the formations and where to get lined up and who’s going to be where — just real vanilla stuff.

“Now, being able to see where we left off, at a pretty intensive game plan, seeing how guys handle it. To have that core of our group back and be able to break that down and move on from there is definitely big for us — very big for us.”

Even in tough times last season, Nagy exuded a confidence that he knows where Trubisky and this offense are headed. He seemed more interested in laying a foundation that would grow the offense for the long term rather than lean on a hot combination that might produce more immediate results. Nagy’s offense is a long way from maturity, but the second step should be a pretty big one.

So while there will be a lot of focus on the coach who succeeds Fangio, most of the pressure will be on Nagy in 2019. If the Bears’ offense doesn’t take a quantum leap in Year 2 and the Bears falter, Nagy, Trubisky and the offense likely will be the culprits more than Fangio’s successor.